Ok - taken some pics - apolagies tho because a bit rushed and lighting not really quite showing as much detail as I'd like. Suffice to say tho - here we see similar pattern tho, not much displacement - mostly ''rub'' type appearance - no real burrs to be felt.
The light color frame is of course my #1, with approx 300 thru. The gray frame is #2 and that has only about 100 approx thru it. I reckon this effect will show very early possibly.
The first two pics are attempts to show the main wear area, similar to Datan's pics of that area.
The third is a side view, taken because I want to raise a point. I am adding more commentary after pics .....
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OK now, here is what I am thinking. First off steel/aluminum - no contest re hardness so even with lube, enough pressure can and will lead to some change in frame surface. I reckon that any rub at all - slightest - will perforce leave some marking on anodizing .... even slightly removing same. That tho is just miniscule rubbing.
Now, looking at what leads to this main wear appearance, I am of opinion - for now at least - that this is caused by the under side of chamber area - either side of lug. During firing cycle, barrel unlocks as soon as slide proceeds rearwards .... and then as slide returns it again locks up. Once unlocking then I see the probablility of some slight downward movement and I think it is the slight ''impact'' rub from this that is causing the wear.
Because of this I do not see the wear as overly prejudicial and it will possibly be self limiting over time.
I placed that third pic to provoke thought over the prime required integrity - which is slide on rails. I can see no wear on my rails at all - the most is a small anodic ''scuff'' on the darker frame rail in view.
Now if I saw wear on the rails I would be concerned - but here we have tight tolerances, and proper lube will prevent any problem because we have linear sliding motion and little else.
The barrel unlocking produces a different stress - not a stress that will lead to any failure - just a stress resulting in a slight ''slamming'' of chamber base against frame twice each cycle, with perhaps a slight ''shuffle'' too. In fact unlocking may be more to blame - or locking may be so - hard to tell - let's assume both have equal effect for now.
Do you see where I am coming from here? I am not trying to say it is a desirable trait to see per se - but looking at the mechanics, stresses, materials and results - do not see this as overtly prejudicial.
I shall still be interested to know the R Bros take - I am also interested to see what Eric might say when looking at his early gun which has had IIRC over 5k rounds thru it. Is that showing same? Is it any worse?
I'll leave this here for now and think further but this is where I am at right now. Open to any input.
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BTW meant say - sorry about some crud showing!! I did a very quick wipe over to get rid of surplus lube but did not continue to produce a pristeen state! Too much to do this evening.
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